Nasolacrimal duct obstruction is the obstruction of the

nasolacrimal duct The nasolacrimal duct (also called the tear duct) carries tears from the lacrimal sac of the eye into the nasal cavity. The duct begins in the eye socket between the maxillary and lacrimal bones, from where it passes downwards and backwards. The ...

and may be either

congenital A birth defect, also known as a congenital disorder, is an abnormal condition that is present at birth regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities can ...

or acquired. Obstruction of the nasolacrimal duct leads to the excess overflow of

tears Tears are a clear liquid secreted by the lacrimal glands (tear gland) found in the eyes of all land mammals. Tears are made up of water, electrolytes, proteins, lipids, and mucins that form layers on the surface of eyes. The different types of ...

called epiphora.

Sign and symptoms

Excessive tearing is the most common complaint of patients with nasolacrimal duct obstruction, followed by acute or chronic infections. Pain at the side of the nose suggests

dacryocystitis Dacryocystitis is an infection of the lacrimal sac, secondary to obstruction of the nasolacrimal duct at the junction of lacrimal sac. The term derives from the Greek ''dákryon'' ( tear), ''cysta'' (sac), and ''-itis'' (inflammation). It causes ...

. Nasolacrimal duct obstruction is more common with increasing age and more common in females than males.

Cause

Involutional stenosis

Involutional

stenosis A stenosis (from Ancient Greek στενός, "narrow") is an abnormal narrowing in a blood vessel or other tubular organ or structure such as foramina and canals. It is also sometimes called a stricture (as in urethral stricture). ''Stricture'' ...

is probably the most common cause of nasolacrimal duct obstruction in older people. It affects women twice as frequently as men. Although the inciting event in this process is unknown, clinicopathologic study suggests that compression of the lumen of the nasolacrimal duct is caused by inflammatory infiltrates and

edema Edema, also spelled oedema, and also known as fluid retention, dropsy, hydropsy and swelling, is the build-up of fluid in the body's Tissue (biology), tissue. Most commonly, the legs or arms are affected. Symptoms may include skin which feels t ...

. This may be the result of an unidentified infection or possibly an

autoimmune disease An autoimmune disease is a condition arising from an abnormal immune response to a functioning body part. At least 80 types of autoimmune diseases have been identified, with some evidence suggesting that there may be more than 100 types. Nearly a ...

Dacryolith

Dacryoliths or cast formation, within the lacrimal sac can also produce obstruction of the nasolacrimal duct.

Sinus disease

Sinus disease often occurs in conjunction with, and in other instances may contribute to the development of nasolacrimal duct obstruction. Patients should be asked about previous sinus surgery, as the nasolacrimal duct is sometimes damaged when the maxillary sinus ostium is being enlarged anteriorly.

Trauma

Naso-orbital fractures may involve the nasolacrimal duct. Early treatment by fracture reduction with stenting of the entire lacrimal drainage system should be considered. However, such injuries are often not recognized or are initially neglected as more serious injuries are managed. In such cases, late treatment of persistent epiphora usually requires dacryocystorhinostomy.

Inflammatory disease

Granulomatous disease, including

sarcoidosis Sarcoidosis (also known as ''Besnier-Boeck-Schaumann disease'') is a disease involving abnormal collections of inflammatory cells that form lumps known as granulomata. The disease usually begins in the lungs, skin, or lymph nodes. Less commonly af ...

granulomatosis with polyangiitis Granulomatosis with polyangiitis (GPA), previously known as Wegener's granulomatosis (WG), is a rare long-term systemic disorder that involves the formation of granulomas and inflammation of blood vessels (vasculitis). It is a form of vasculitis ...

, and midline granuloma, may also lead to nasolacrimal duct obstruction.

Lacrimal plugs

As with similar cases of canalicular obstruction, dislodged punctual and canalicular plugs can migrate to and occlude the nasolacrimal duct.

Neoplasm

Neoplasm A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

should be considered in any patient presenting with nasolacrimal duct obstruction. In patients with atypical presentations, including younger age and male gender, further workup is appropriate. Bloody punctual discharge or lacrimal sac distension above the medial canthal tendon is also highly suggestive of neoplasm.

Congenital

Congenital nasolacrimal duct obstruction, or dacryostenosis, occurs when the lacrimal duct has failed to open at the time of birth, most often due to an imperforate membrane at the valve of Hasner.Blocked tear ducts in infants, Pediatric Views, June 2006 http://www.childrenshospital.org/views/june06/blocked_tear_ducts.html Around 6% of infants have congenital nasolacrimal duct obstruction, or dacryostenosis, usually experiencing a persistent watery eye even when not crying. If a secondary infection occurs (

Dacryocystitis Dacryocystitis is an infection of the lacrimal sac, secondary to obstruction of the nasolacrimal duct at the junction of lacrimal sac. The term derives from the Greek ''dákryon'' ( tear), ''cysta'' (sac), and ''-itis'' (inflammation). It causes ...

), purulent (yellow / green) discharge may be present. Most cases resolve spontaneously, with

antibiotic An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of ...

s reserved only if

conjunctivitis Conjunctivitis, also known as pink eye, is inflammation of the conjunctiva, outermost layer of the white part of the eye and the inner surface of the eyelid. It makes the eye appear pink or reddish. Pain, burning, scratchiness, or itchiness may ...

occurs. Lacrimal sac massage has been proposed as helping to open the duct, though this is not always successful. The aim of massage is to generate enough hydrostatic pressure (downward, toward the nose) to "pop" open any obstruction. Additional massage may then be performed up toward the

lacrimal punctum The lacrimal punctum (plural ''puncta'') or lacrimal point, is a minute opening on the summits of the lacrimal papillae, seen on the margins of the eyelids at the lateral extremity of the lacrimal lake. There are two lacrimal puncta in the medial ( ...

, in order to express any infectious material out of the

nasolacrimal sac The lacrimal sac or lachrymal sac is the upper dilated end of the nasolacrimal duct, and is lodged in a deep groove formed by the lacrimal bone and frontal process of the maxilla. It connects the lacrimal canaliculi, which drain tears from the ey ...

. When discharge or crusting is present, the lids should be gently cleaned using cooled pre-boiled water or saline. Referral to an

ophthalmologist Ophthalmology ( ) is a surgery, surgical subspecialty within medicine that deals with the diagnosis and treatment of eye disorders. An ophthalmologist is a physician who undergoes subspecialty training in medical and surgical eye care. Followin ...

is indicated if symptoms are still present at 12 months, or sooner if significant symptoms or recurrent infections occur. Nasolacrimal duct probing may be performed in the office setting (usually from 4 to 8 months of age) or under general anesthesia in an operating room for older patients. The success rate of probing is higher for younger children. A

silastic Silastic (a portmanteau of ' silicone' and 'plastic') is a trademark registered in 1948 by Dow Corning Corporation for flexible, inert silicone elastomer. Composition The Silastic trademark refers to silicone elastomers, silicone tubing and some c ...

tube or

stent In medicine, a stent is a metal or plastic tube inserted into the lumen of an anatomic vessel or duct to keep the passageway open, and stenting is the placement of a stent. A wide variety of stents are used for different purposes, from expandab ...

may be employed along with probing to maintain tear duct patency. A systematic review comparing immediate probing with deferred probing found that in children with unilateral nasolacrimal duct obstruction, immediate probing resulted in a higher success rate of treatment compared to deferred probing.

Diagnosis

Evaluation is in the form of a dye disappearance test followed by irrigation test. By using this sequence (with modifications) as a guide, the physician can frequently streamline diagnostic testing.

Dye disappearance test

The dye disappearance test is useful for assessing the presence or absence of adequate lacrimal outflow, especially in unilateral cases. It is more heavily relied upon in children, in whom lacrimal irrigation is impossible without deep sedation. Using a drop of sterile 2% fluorescein solution or a moistened fluorescein strip, the examiner instills fluorescein into the conjunctival fornices of each eye and then observes the tear film, preferably with the cobalt blue filter of the slit lamp. Persistence of significant dye and, particularly asymmetric clearance of the dye from the tear meniscus over a 5-minute period indicate an obstruction. If the dye disappearance test result is normal, severe lacrimal drainage dysfunction is highly unlikely. The Jones tests are variations of the dye disappearance test.

Irrigation test

In irrigation test, a lacrimal irrigation cannula is passed into the punctum and advanced through the canaliculus to the lacrimal fossa. Clear water or saline is then irrigated through the cannula. If fluid passes into the nose without reflux out of the opposite canaliculus, the system is patent. If no fluid passes but it all comes back through either punctum, nasolacrimal duct obstruction is present.

Management

Intubation and stenting

Some clinicians believe that partial stenosis of the nasolacrimal duct with symptomatic epiphora sometimes responds to surgical intubation of the entire lacrimal drainage system. This procedure should be performed only if the tubes can be passed easily. In complete nasolacrimal duct obstruction, intubation alone is not effective, and a dacryocystorhinostomy should be considered.

Dacryocystorhinostomy

dacryocystorhinostomy Dacryocystorhinostomy (DCR) is a surgical procedure to restore the flow of tears into the nose from the lacrimal sac when the nasolacrimal duct does not function. Process Traditional A small incision is made on the side of the nose and some bone ...

is the treatment of choice for most patients with acquired nasolacrimal duct obstruction. Surgical indications include recurrent dacryocystitis, chronic mucoid reflux, painful distension of the lacrimal sac, and bothersome epiphora. For patients with dacryocystitis, active infection should be cleared, if possible, before a dacryocystorhinostomy is performed.

References

External links

{{Eye pathology Congenital disorders of eyes Eye Disorders of eyelid, lacrimal system and orbit